1. Technical Field
The present invention relates to an inkjet recording method and an inkjet recording device.
2. Background Art
As inkjet ink, dye ink has been mainly used in terms of coloring and reliability. However, at the same time, such a dye ink has disadvantages about water-resistance, light resistance, etc. For this reason, pigment ink has become popular as a substitute recently.
However, since pigment ink is attached to the uppermost surface of a printed matter (hereinafter referred to as pigment ink printed matter) on which texts and/or images are printed by using pigment ink, the texts and images are easily peeled off, meaning that the friction resistance of the pigment ink printed matter is inferior.
In attempts to improve the friction resistance of such a pigment ink printed matter, for example, JP-2011-63016-A and JP-2011-105900-A disclose methods of protecting (fixing) the surface of a printed matter by discharging transparent post-processing fluid onto a recorded portion of pigment ink to form a film which covers the recorded portion.
However, since a typical image forming method applies such transparent ink to all over the recorded portion, the quality of images deteriorates by transfer contamination to a transfer roller in a high-speed printing system in particular. Moreover, printed continuous paper is reeled again after printing, which causes attachment of contact surfaces of the paper (so-called blocking phenomenon).
Currently, the quality of images on a par with conventional offset printing is in demand to such an inkjet ink recording method even for coated paper having low ink absorption for use in commercial printing. However, since such coated paper has a surface structure not suitable to absorb ink, the quality of images tends to be bad and blocking phenomenon easily occurs due to transfer contamination.
Moreover, JP-4066338-B1 (JP-2004-181688-A) discloses a recording method of changing the amount of overcoat applied to an image after image forming. In this method, yellow ink is overcoat to prevent bronzing and improve the color reproducibility but not to reduce transfer contamination or improve blocking resistance.
In addition, JP-2008-18664-A discloses an inkjet recording method of applying processing fluid after ink is applied, in which the application amounts of the ink and the processing fluid are reduced for duplex printing relative to simplex printing and the reduction rate of the processing fluid is larger than that of the ink.
However, this is to prevent strike-through of images printed on plain paper but not used for coated paper having a low absorption of ink for use in commercial printing.